Using Nutrition to Manage and Prevent Stomach Ulcers in Horses

between meals and while acid is still being secreted in the stomach no saliva is being produced because the horse is not eating anything. Thus no buffer is sent to the stomach to help protect the squamous section. Therefore the timing between meals should be kept in mind when feeding horses.
Horses that are fed diets high in sugar and starch such as highgrain diets have an increased risk for ulcer development. These starches are rapidly fermented by resident microbes in the gastrointestinal tract and produce acid byproducts which make the stomach environment even more acidic. Furthermore grains both textured and pelleted do not require as much chewing as forages leading to smaller quantities of saliva produced for a shorter amount of time. So not only will the ingestion of grains produce a more acidic stomach environment than forages but they also do not cause as much secretion of saliva to help buffer the stomach.
Ulcer Diagnosis 
The only way to be sure ulcers are present is to have a veterinarian perform a gastroscopy Figure 2. This process involves a camera that can be placed in the gastrointestinal tract via the nostril. Horses are usually fasted before this procedure to ensure most surfaces within the stomach can be observed. This process helps veterinarians see if ulcers are present and allows them to give the ulcers scores based on overall ulceration severity Figure 3 4. Below is a table of how squamous ulcers are scored within the stomach with grade 1 ulcers being mild and grade 4 ulcers being the most extensive. 
Table 1 Scoring system of squamous ulcers used in the United States and in Europe American Association of Equine Practitioners.

Grade	Squamous Mucosa Description
0	The epithelium is intact and there is no appearance of thickening.
1	The mucosa is intact, but there are areas where the epithelium is thickening.
2	Small, single, or several distinct lesions.
3	Large single or extensive superficial lesions.
4	Extensive lesions with areas of apparent deep ulceration.

Treatment of Squamous Ulcers

GastroGard also known as omeprazole is the only medication on the market in the United States that is FDA approved to treat squamous ulcers in horses. Omeprazole works to reduce the production of stomach acid by inhibiting a proton pump within the stomach that is responsible for secretion of stomach acid. It is not just a buffer for stomach acid. Usually a 28day treatment with this medication is prescribed by a veterinarian. This medication can also be given at half dose sold as UlcerGard with no prescription required to aid in the prevention of ulcers. It is important to use GastroGard and not medication intended for human ulcers when treating ulcers in horses because GastroGard has a special coating to ensure that it is not degraded by the time it reaches the small intestine where it is absorbed. While GastroGard is effective successful treatment and particularly prevention of future ulcers requires nutritional changes as well.

Feeding Practices to Reduce Risk of Squamous Ulcers
While omeprazole will help heal existing squamous ulcers successful management and prevention of future ulcers requires a combination of both medication and nutritional management. Some nutritional management steps include

Feed multiple smaller grain andor concentrate meals throughout the day. By rationing the grain into 3 or 4 meals per day the increased acidity of the stomach that follows a large grain meal can be avoided. When horses eat a grain meal they do not chew as much and thus not much saliva will be produced to buffer the stomach acid.

Ensure your horse has constant access to forage. Provide at least 1 5 of a horses bodyweight in dry matter DM of forage hay andor pasture per day. For example a 1000pound horse should receive at least 15 pounds of forage per day 0 15 x 1000.
Forage requires
more chewing and thus more saliva is secreted compared to a grain or concentrate meal. In addition the long fiber particles form a mat that floats on top of the stomach contents helping to prevent the acidic layer from splashing up into the squamous section. If possible a horse should have 247 access to forage. By providing forage throughout the day both the saliva and forage act as a buffer against stomach acid and can decrease the risk of squamous ulcers developing. If free access to forage is not possible the use of a slow feed hay net can be used as it increases the horses time spent foraging and chewing.
Avoid feeding more than 1 gram of sugar and starch listed as sugar and starch separately on a feed tag per kilogram of bodyweight BW per meal and 2 grams of sugar and starch per kilogram of bodyweight per day.
For example if you are feeding a 1000pound horse about 450 kilograms then they should receive no more than 450 grams of sugar and starch per meal 450 kg BW x 1 gram sugar and starch and no more than 900 grams of sugar and starch per day 450 kg BW x 2 grams sugar and starch.
If the horse is eating a hay that contains 10 sugar and starch assuming the horse is eating 1 5 of their bodyweight then the horse is consuming 1 5 pounds of sugar and starch from the hay per day 681 gramsday. This leaves about 219 grams left per day that can be supplied through the grain.
Lets say you are feeding a grain that has a combined sugar and starch level of 15. Every pound of feed will have 0 15 pounds of sugar and starch. If one pound is about 450 grams then one pound of feed
will have 68 grams of sugar and starch 0 15 x 450. This means that the horse should receive less than 3 2 pounds of that grain per day 219683 2.